Your experience seems to indicate that handsomeness and being a jerk are independent variables. In other words, the looks of someone don’t give you any information on how mean or kind they are.
Are you mostly going on blind dates or dating people you haven’t met before in real life? If so, that might be part of the problem. In those cases you cannot know whether someone is nice or not until you’re actually meeting them at a date.
I think one can usually filter out a lot of jerks if one meets new people through friends. After all, friends can do a first filtering for you and will most likely not connect you with people they know are jerks. But I understand that depending on your circumstances this may not work.
Anyway, I’m really out of my area of expertise here. As I said, I’m not a dating expert. But I wish you good luck in finding a sweetie, Susan!